The preparation method of microencapsulated ammonium polyphosphate
Technical field
The present invention relates to the ammonium polyphosphate is core material, the microcapsule technology of being wrapped up, particularly a kind of preparation method of microencapsulated ammonium polyphosphate.
Background technology
The general formula of ammonium polyphosphate (ammonium polyphosphate is hereinafter to be referred as APP) is (NH
4)
N+2P
nO
3n+1, when n is enough big, can be written as (NH
4PO
3)
nThe relative molecular weight of structural unit is 97.01, and theoretical phosphorus content is 31.92%, and theoretical nitrogen content is 14.44%.
APP is a kind of powder object of flowability normally, and its phosphorus content and nitrogen content are all very high, has the P-N synergistic effect between them again, thereby has high flame-retarded efficiency.Its Heat stability is good, product is bordering on neutrality, can carry out its flame retardant properties of composite raising with many other fire retardants, and the amount of being fuming is little, and toxicity is little, thereby person is arranged, and it is " environment friendly flame retardant ".
At present, be used for flame retardant plastics, rubber, the APP of superpolymer such as fiber mainly is II type APP, and there is a certain amount of P-O-P crosslinking structure in the I type APP that extensively uses before ining contrast between II type APP molecular chain, the polymerization degree can reach more than 1000, belong to the tiltedly symmetrical crystallographic system in side, rule of surface, initial decomposition temperature can reach more than 270 ℃.
Yet, II type APP still exists some shortcomings: on the one hand, because II type APP still is a mineral compound, addition is big, poor with the organic polymer consistency, on the other hand, owing to have the oxygen key on the ammonium polyphosphate chemical structure, and the oxygen key is often arranged to outside surface, form easily absorption water molecules, cause APP that certain moisture is arranged, can absorb airborne moisture when depositing in the air, cause APP that hydrolysis reaction takes place gradually, the adding of APP has simultaneously often changed the perviousness of material, and under high relative humidity condition, water vapor permeation enters in the APP fire retardant material, make the interior mutually APP dissolving of body and, cause material to play " bloom " to external migration, problems such as the not durable and electric property of the flame retardant resistance of material is abominable.
At the shortcoming that above-mentioned APP exists, a large amount of patents has been described II type APP has been carried out the surface of microcapsule processing both at home and abroad, so that better bring into play the effect of APP fire retardant.
US5700575, US4396586, patent disclosures such as US5213783 with melamino-formaldehyde resin parcel II type APP, preparation have resistance to hydrolysis can, the method for the II type APP that improves consistency.Do not compare with the II type APP through parcel, its water-soluble and consistency has some improvement.But, adopt disclosed method to carry out the surface parcel and handle, at first, encapsulation process is to carry out in kneader, the response characteristic of powder and powder causes reaction not exclusively inhomogeneous with reaction easily, and the interface of APP can not all evenly be wrapped completely; Secondly, the APP behind the parcel, the obvious chap of median size, even have the fritter aggregate to form, and before using, must can cause so again wrapping up the destruction at interface through pulverizing once more, the APP surface is exposed again.
In order to solve the problem that above-mentioned parcel occurs, US6251961B1, DE3439233, CA2082873, US5321057, patents such as EP0542373A1 propose, APP is dispersed in the corresponding solvent, adopts melamino-formaldehyde resin or similar resin that APP is wrapped up then.Concrete grammar is in the reactor that stirs and reflux is housed, APP is dispersed in the solvent, add melamine, formaldehyde and solidifying agent or melamine formaldehyde (MF) performed polymer and solidifying agent then, carry out encapsulation reaction under the temperature of solvent refluxing, the reaction times is 200-300 minute.Adopt these class methods can solve the problem of above-mentioned appearance reaction homogeneity and the obvious chap of particle, but, still there is shortcoming in this method, on the one hand, in encapsulation process, because small molecules formaldehyde is excessive, there is excessive free formaldehyde among the parcel APP, for being applied in the superpolymer in the future, can cause the problem of processing and the performance of destroying material, on the other hand, himself character of melamino-formaldehyde resin determines that the consistency of itself and superpolymer is insuperior, and it is limited to use its parcel APP to improve performance.
Shortcoming at above-mentioned parcel appearance, DE3217816, patents such as US4514328 propose with Resins, epoxy II type APP to be carried out the surface parcel, the Resins, epoxy of its selection is pure dissolubility, it is by dibasic alcohol or polyvalent alcohol and 3-chloro-1,2-propylene oxide or the condensation of dichloro glycol and obtain adopt correspondent alcohol dissolubility solidifying agent to be cured simultaneously.The II type APP of the II type APP contrast melamino-formaldehyde resin parcel behind the parcel, it is water-soluble lower, and better with the consistency of superpolymer, electrical property also improves significantly.But because wrap Resins, epoxy and its pure dissolubility of solidifying agent are fine, the integument after it solidifies also has the pure dissolubility of part, causes the compactness defectiveness of parcel efficient and integument.
Summary of the invention
In order to overcome the shortcoming of above-mentioned prior art, the invention provides a kind of preparation method of microencapsulated ammonium polyphosphate.This method can improve APP and superpolymer consistency, reduce APP water-soluble, improve its electric property, improve the compactness of parcel efficient and integument.
The technical scheme that the present invention takes is:
A kind of preparation method of microencapsulated ammonium polyphosphate is a core with the ammonium polyphosphate, and with epoxy resin micro-capsule parcel ammonium polyphosphate, concrete preparation method is as follows:
(1) in the reactor that has stirring and reflux, ammonium polyphosphate powder suspended dispersed in solvent, is added bisphenol A epoxide resin again, and stir;
(2) add hot suspension, under the little situation of boiling of suspension, add amine curing agent, reacted 2~10 hours, make epoxy resin cure in the mode that drips;
(3) after the reaction end, reactant is cooled to 40~60 ℃, filters then, under nitrogen environment, 90~120 ℃ further solidify down and the dry filter product, had both got microencapsulated ammonium polyphosphate;
The reinforced weight ratio of described ammonium polyphosphate and bisphenol A epoxide resin is 1:0.02~0.1; Preferred weight ratio is 1:0.03~0.08;
The weight ratio of described ammonium polyphosphate and solvent is 1:1.5~4; Preferred weight ratio is 1:2~3.
The epoxy mole number of described bisphenol A epoxide resin: amine curing agent ammonia value mole number is 1:0.8~1.5;
Described bisphenol A epoxide resin is a kind of among E54, E51, the E44.
Described epoxy curing agent is an amine curing agent, and amine curing agent is a kind of in polyetheramine, silane coupling agent γ-An Bingjisanyiyangjiguiwan (KH550), silane coupling agent γ-glycidyl ether oxygen propyl trimethoxy silicane (KH560), the amido silicon oil etc.
Described solvent is selected from fatty alcohol or the aliphatic ketone that contains 1~4 carbon atom.
Described fatty alcohol is a kind of in methyl alcohol, ethanol, propyl alcohol, the butanols, and aliphatic ketone is a kind of in acetone, the methylethylketone.
The present invention is to be raw material with bisphenol A epoxide resin and amine curing agent, be equipped with stir and the reactor of reflux in APP is wrapped up.According to the present invention, APP: bisphenol A epoxide resin: solvent=1:0.03~0.3:1.5~4.Solvent load is too high, solvent recuperation energy consumption height, and it is too high to wrap up required cost; Solvent load is low excessively, and APP, Resins, epoxy and the solidifying agent dispersion effect in solvent is not good enough, causes reunion easily, causes parcel inhomogeneous, finally influences the parcel effect of APP integral body.Employed solvent can be repeatedly used after reclaiming, and does not influence the quality of product wrapping.The consumption of Resins, epoxy and solidifying agent is too high, and on the one hand, the integument of APP particle surface is blocked up, and cost improves; On the other hand, Resins, epoxy itself is exactly inflammable resin, introduces too much Resins, epoxy and is wrapped in the APP surface, can cause the APP flame retarding efficiency to descend; The consumption of Resins, epoxy and solidifying agent is low excessively, can cause the parcel of APP particle surface inentirely, has the APP particle of part still exposed, causes negative effect still to exist.Utilize the microencapsulated ammonium polyphosphate of method preparation of the present invention to compare with the ammonium polyphosphate that does not wrap up, the particulate free-running property is good, improve with the consistency of superpolymer, particulate is water-soluble significantly reduces, electric property improves significantly, and has that parcel is closely knit, consistency good, water-soluble low, advantage that electrical property is excellent.The fire retardant that can be used for macromolecular materials such as polyolefine.
With the microcapsule parcel APP of the inventive method preparation, by the infrared spectrum contrast, the characteristic peak of Resins, epoxy has appearred in the APP behind the microcapsule parcel; Use scanning electron microscopic observation, the APP surface wrap film behind the parcel is fine and close and even, and granular size is average, finds no exposed APP particle; APP free-running property behind the parcel is good, and grain diameter remains unchanged substantially.
Embodiment
Further specify the present invention with example below, but the present invention is in no way limited to these embodiment.
Embodiment 1
In the 2L reactor that has stirring and reflux, adding 200g APP is suspended in the 350ml dehydrated alcohol, drip 8g bisphenol A epoxide resin E51 again, suspension is heated to little boiling, continue dispersed with stirring APP and E51 30min, in 30min, drip the alcoholic solution (the 2.45g polyetheramine is dissolved in the 50ml dehydrated alcohol) of 2.45g polyetheramine, under the little condition of boiling of dehydrated alcohol, stir, reacted 3 hours, make epoxy resin cure, filter then, under nitrogen environment, 100 ℃ further solidify down and the dry filter product, have both got the parcel APP 206.34g of form and Diaspora Performance excellence.
Embodiment 2
In the 1L reactor that has stirring and reflux, adding 100g APP is suspended in the 300ml anhydrous propanone, Dropwise 5 g bisphenol A epoxide resin E44 again, suspension is heated to little boiling, continue dispersed with stirring APP and E44 30min, in 30min, drip the alcoholic solution (the 1.15g polyetheramine is dissolved in the 25ml anhydrous propanone) of 1.15g polyetheramine, under the little condition of boiling of anhydrous propanone, stir, reacted 6 hours, make epoxy resin cure, filter then, under nitrogen environment, 100 ℃ further solidify and the dry filter product, have both got the parcel APP 105.18g of form and Diaspora Performance excellence.
Embodiment 3
In the 2L reactor that has stirring and reflux, adding 200g APP is suspended in the 500ml anhydrous methanol, drip 6.5g bisphenol A epoxide resin E51 again, suspension is heated to little boiling, continue dispersed with stirring APP and E51 30min, in 30min, drip the alcoholic solution (3.25g KH550 is dissolved in the 50ml anhydrous methanol) of 3.25g KH550, under the little condition of boiling of anhydrous methanol, stir, reacted about 8 hours, make epoxy resin cure, filter then, under nitrogen environment, 120 ℃ further solidify and the dry filter product, have both got the parcel APP 207.33g of form and Diaspora Performance excellence.
Embodiment 4
In the 20L reactor that has stirring and reflux, adding 2000g APP is suspended in the 8000ml dehydrated alcohol, drip 80g bisphenol A epoxide resin E51 again, suspension is heated to little boiling, continue dispersed with stirring APP and E51 30min, in 30min, drip the alcoholic solution (the 80g amido silicon oil is dissolved in the 500ml dehydrated alcohol) of 80g amido silicon oil, under the little condition of boiling of dehydrated alcohol, stir, reacted 2 hours, make epoxy resin cure, filter then, under nitrogen environment, 110 ℃ further solidify and the dry filter product, have both got the parcel APP 2103.72g of form and Diaspora Performance excellence.
Embodiment 5
In the 500L reactor that has stirring and reflux, adding 100kg APP is suspended in the 250L dehydrated alcohol, drip 8kg bisphenol A epoxide resin E51 again, suspension is heated to little boiling, continue dispersed with stirring APP and E51 30min, in 30min, drip the alcoholic solution (the 2.45Kg polyetheramine is dissolved in the 50L dehydrated alcohol) of 2.45Kg polyetheramine, under the little condition of boiling of dehydrated alcohol, stir, reacted 7 hours, make epoxy resin cure, filter then, under nitrogen environment, 90 ℃ further solidify and the dry filter product, have both got the parcel APP 108.45Kg of form and Diaspora Performance excellence.
The ammonium polyphosphate that uses in the foregoing description is II type ammonium polyphosphate (II type APP): 1500 purpose white powders.
Test data among the present invention among each embodiment records by following method:
1, size and distribution: S3500 measures with U.S. MICROTRAC laser light scattering particle size analyzer.
2, particle form analysis:, observe under magnification 200 conditions with the Sirion20 type scanning electron microscope of Dutch Philips company.
3, the particle chemical functional group analyzes: with the U.S. ESP of LEC0 company type Fourier transformation infrared spectrometer, adopt the KBR compressing tablet to observe.
4, viscosity measurement: respectively 30g or 10gAPP are suspended in the 70g water or 90g dioctyl phthalate (DOP) (DOP) under 80 ℃, fully stir 5min, be cooled to 25 ℃ then, measure its viscosity with Rotary Viscosimeter again.
5, solubility test: the 10gAPP sample is suspended in the 100ml distilled water, and under 25 ℃ and 60 ℃, constant temperature stirs 20min.Use the centrifugal 40min of whizzer then.Make do not dissolve the APP sample be deposited in the bottom.Get supernatant liquid 5.0ml, feed in the furnace pot of known quality, 120 ℃ of dryings, the residual quality of weighing is calculated water soluble fraction from the residue amount, gets the water soluble fraction massfraction.
6, water resistance test: the combustionproperty testing standard sample of preparation is formed in 70 ℃ the temperature and soaks 168h, in the cryodrying case, dry then, be used for the combustionproperty test.
7, dialysis property testing: APP and 80 parts of PP after 20 parts of processing, through the twin screw extruder granulation, make test piece (100mm*100mm*1.6mm).This sheet soaks 4h in 95 ℃ of hot water, measure the surface resistivity of hot-water soak front and back.
8, Mechanics Performance Testing: tensile property is tested by ASTM D638, and cantilever fine strain of millet notched Izod impact strength is tested by ASTM D256, and modulus in flexure is tested by ASTM D790, and melting index is tested by ASTM D1238.
9, the vertical combustion grade is measured: the vertical combustion experiment experimentizes according to the UL94 standard.
Table 1 degree test result
Product |
Viscosity (H
2O)(Mpa·s)
|
Viscosity (DOP) (Mpas) |
Do not wrap up APP |
127.3 |
168.9 |
Embodiment 1 |
70.5 |
105.6 |
Embodiment 2 |
75.3 |
112.2 |
Embodiment 3 |
54.7 |
83.1 |
Embodiment 4 |
65.2 |
97.0 |
Embodiment 5 |
60.0 |
90.2 |
Table 2 degree of separating test result
Table 3 dialysis property testing result
By mass ratio PP:APP: the prescription of self-control carbon forming agent=68:25:7 carries out extruding pelletization, is injection molded into the needed standard batten of test then.
Table 4 Mechanics Performance Testing result
Product |
Tensile strength (Mpa) |
Elongation at break (%) |
Notched Izod impact strength (J/m) |
Modulus in flexure (Mpa) |
Melting index (g/10min) |
PP |
35 |
870 |
23 |
1400 |
10 |
Do not wrap up APP |
20 |
33 |
18 |
1927 |
6.6 |
Embodiment 1 |
20 |
35 |
20 |
1922 |
6.7 |
Embodiment 2 |
21 |
36 |
20 |
1944 |
7.0 |
Embodiment 3 |
24 |
67 |
25 |
1977 |
8.7 |
Embodiment 4 |
23 |
44 |
22 |
1953 |
7.7 |
Embodiment 5 |
23 |
58 |
23 |
1993 |
7.7 |
Table 5 flame retardant test result